The present invention relates to machines that accept chemical specimens or samples and extract fluid containing volatile components from the chemical samples for later analysis. More particularly, the invention relates to machines that accept vials that carry such specimens, which machines convey the fluid or at least the volatiles therein to a chemical species analyzer such as a gas chromatograph.
Gas chromatographs and similar chemical species analyzers such as mass spectrometers are known. Vial handling machines, such as the model 7000 Headspace Autosampler sold by Tekmar Co., Cincinnati, Ohio, USA, are also known. The model 7000 extracts from a covered vial a predetermined amount of fluid from a static gaseous headspace above a sample, and conveys the predetermined amount of fluid (containing volatiles to be identified) to a gas chromatograph. Vial autosamplers using dynamic headspace techniques are also known, such as the model PTA-30W/S Autosampler sold by Dynatech Precision Sampling Corp., Baton Rouge, La., USA. The model PTA-30W/S routes a purge gas into a covered vial containing a sample, and provides an outlet from the vial to carry the exiting fluid (comprising the purge gas and volatile components from the sample) to a separate concentrator trap unit. After the volatile components are collected on the trap, they are flushed into a gas chromatograph for analysis. The model PTA-30W/S can also extract a liquid sample containing volatiles from a covered vial and transfer it to a separate unit which sparges the liquid sample and traps the volatile components, for later transfer to a gas chromatograph.